Hull cleaner



May 17, 1966 w. R. CRAWFORD m HULL CLEANER 2 Sheets-Sheet Filed Jan. 8, 1965 INVENTOR. W/LL/AM R. (RAW/ 0?!) H ATTORNEYS y 7, 1966 w. R. CRAWFORD in 3,251,331

HULL CLEANER 2 Shee'bs-Sheet 2 Filed Jan. 8, 1965 FIE--5- FIE--4- INVENTOR- WILLIAM R. CKAW/WED, 1E

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ATTORNEYS United States Patent 3,251,331 HULL CLEANER William R. Crawford 11!, 278 Argonne Ave., Long Beach, Calif. Filed-Jan. 8, 1965, Ser. No. 425,678 6 Claims. (Cl. 114-222) This application is a continuation-in-part of my application Serial No. 314,417, filed October 7, 1963.

This invention'relates in general to an apparatus for removing sea growths from the hulls of vessels while said hulls are under water and more particularly to apparatus which is dependent upon inducing rapid flow of water over a surface supporting sea growths to achieve the aforementioned cleaning action.

Barnacles, weeds, and the like impair the efficiency of vessels and may seriously reduce the possible speed as a result of which vessels are generally taken into dry dock periodically to eifect a thorough cleaning. This is time consuming, and because of the need for lifting the vessels from the water, expensive.

It is an object of this invention to provide a method for cleaning hulls of vessels without requiring that the vessels be moved out of the water.

It is a further object of this invention to provide a method for cleaning the hulls of vessels in a relatively rapid fashion.

Still another object of this invention is to provide an apparatus of the foregoing type which is capable of governing its position relative to a generally vertical surface by harnessing'a force component generated through its operation, thus to prevent the apparatus from moving downwardly under the influence of gravity and to insure proper contact between the apparatus and the surface being cleaned.

Other objects and advantages of this invention, if not specifically set forth, will become apparent during the course of the description which follows.

Generally, this invention comprises an apparatus for removing sea growths from the hulls of vessels when said hulls are under water, the apparatus comprising a carriage having means for maintaining a predetermined orientation of the carriage relative to the hull. Such means is preferably a wheeled carriage having three or four Wheels, although other means may be employed to secure the desired orientation. There is also provided a conduit including generally opposed inlet and outlet ends, said inlet end including a mouth positioned so that, when the device rests on a flat or slightly curved surface, such as the side of a vessel, said mouth will be spaced from said surface sufiiciently to permit water to pass between said mouth and said surface in wiping engagement therewith. There is also provided at least a single nozzle in the conduit directed generally toward the outlet end. Further, there is provided a hose connected at one end with the nozzle and adapted for connection to a source of water under pressure at the other for discharging a jet of water from said nozzle into said conduit toward the outlet end thereof whereby to create a vacuum and induce a flow of outside water between the mouth of the cleaning apparatus and the hull surface adjacent thereto. There are certain critical relationships between the dimensions of such parts as is hereinafter brought out in detail.

In the drawings:

FIGURE 1 is a perspective view of the cleaning apparatus of this invention in use against a hull of a vessel, the latter being shown in fragmentary form.

FIGURE 2 is an enlarged sectional side elevation through the line 2-2 of FIGURE 1.

FIGURE 7 is a diagrammatic view of a cleaner em- I bodying 'the invention with certain critical dimensions indicated thereon.

Referring now to the drawings wherein like characters refer to like parts throughout, there is shown a generally flat surface 10 to be cleaned which surface is encrusted with barnacles and/or other marine growths. The apparatus is used to clean the hull while the vessel remains in the water and, depending upon the opacity of the water and contour of the hull, it may not be possible to see precisely the location of the apparatus relative to the hull.

The apparatus includes acarriage or frame 12 which supports wheels 14. Because of the use of four wheels, each at a corner of the frame, as shown, or, in the alternative, because of the use of three wheels, the apparatus will automatically assume a proper orientation against the hull'of a vesselas long as all wheels are touching the surface 10. Hence, even if the water is so opaque or the area being cleaned is so far removed from the surface that it is not possible to see precisely the fashion in which the apparatus contacts the hull, proper positioning of the apparatus is easily achieved. Connected by means of pivots 16 at either side of the frame is a bar 18 making up part of a yoke having a crossbar at the top 20 to which a supporting handle 22 is attached. This entire yoke and handle assembly permits the cleaning apparatus to be swung in against a side of a ship from a dock or, in the alternative, from the deck of the vessel. The pivotal connections at 16 permit the apparatus to tilt to match the slope of the hull.

-The apparatus includes a nozzle which, as seen in FIGURE 1, is preferably elongated in one dimension, when viewed in plan. The conduit, generally 24, has

opposed inlet 25 and outlet 26 ends, the inlet including; amouth 28 positioned relative to said wheels so that,

when the wheels contact the hull 10, said mouth will be spaced therefrom sufiiciently to permit water to pass between the mouth and the hull surface in wiping engagement with the hull surface so as to dislodge the barnacles 11 or other marine growths.

Positioned in the conduit is at least a single nozzle 30 which is threaded into an adaptor in the side of the conduit, the nozzle including an elbow 32 and being connected to a flexible hose 34 by means-of clamp 36. The hose is secured at the other end by means of clamp 38 to a manifold 40 which is, in turn, capable of being supplied with water under pressure. This assembly provides means for discharging a high speed jet of water from said nozzle 30 into the conduit toward the outlet end of the In operation, when it is desired to clean the hull of a vessel the apparatus is maneuvered into position generally approximating that shown in FIGURE 1. The flow of water is started, as shown by the arrows in FIGURE 2, and the force components generated press the wheels in tightly against the hull. When the layout of parts shown in FIGURES 1 through 3 of the drawings is followed including a 75 angle at the elbow of the nozzle 30 and an angle of 135 between the axis of the mouth of the con duit and the axis of the discharge nozzle together with a A" space between mouth 28 and the surface 10, all other parts being proportioned as shown in FIGURE 2, it is possible to develop force components driving the apparatus against the surface of the craft and upward when submerged. For example, in a device where the parts were proportioned as shown in the drawings, the water pumped through the manifold at the rate of 240 gallons per minute, outside water was sucked in at a rate of 220 gallons per minute with a total flow through the discharge nozzles 42 of 460 gallons per minute. The stream of water through the nozzles 30 produced a vacuum at the mouth of 17 feet of water or 15 inches of mercury. This was sufficient to achieve an excellent cleaning action.

It'is frequently desirable to provide means to cause a traversing action of the cleaning head. For instance, when the layout of the parts is that shown in FIGURES 1 through 3, there is a force directed upwardly on the device so that it tends to move up the side of the vessel. Under many circumstances it is desirable to vary the traversing action, so that the device can be caused to move up or down by remote control. Various means can be used to accomplish this traversing action as is shown in FIGURES 4 through 6.

Referring specifically to FIGURE 4, the discharge throat 50 is provided with a vane or flap 52 which is pivotally connected to the outlet at 54. By altering the angle of the vane, one can cause more or less movement of the device over the hull of the ship. The vane can be controlled by suitable means which may be mechanical, hydraulic or pneumatic. One simple means of controlling the vane is by means of a Bowden cable 55 wherein the control wire 56 is connected to the outer end of the vane, enabling one to move the vane from some remote location.

A preferred means of causing the traversing action is to employ a flexible connection on the water inlet at some point so that the angle at which water enters the device can be varied, thus changing the force which is applied in one direction or another to the device. In the embodiment of FIGURE 5, a flexible connection 58 is inserted between the point where water enters the jet 60 and the supply pipe 62. In FIGURE 6 a flexible connection 64 is inserted some distance on the jet, but still in the proximity of the jet. In either instance, the angle which the supply pipe makes to the device can be varied, as is shown in dot-dash lines, to vary the degree of traverse. In each instance it is important that the flexible connection forms a part of the ejector system, i.e., that positive means be employed between the supply pipe in the ejector to hold these parts in the desired angular relationship. Thus in FIGURE 5 a cable 63 is employed to vary the angle and in FIGURE 6 a cable 65 is employed. Such control means are merely illustrative and it is obvious that other methods might be employed.

In FIGURE 7 the apparatus of the present invention is shown in diagrammatic form with certain critical dimensions indicated thereon. It has been found that when operating within these critical ranges satisfactory results can be attained, while if one attempts to operate outside of these ranges, results will be unsatisfactory.

The critical ranges are given below in the order of importance, it being understood that the first three basic dimensions are essential to the operation of the device, while the remaining dimensions, although preferred and contribute to successful operation, are not nearly as critical and that satisfactory results can be obtained even if one departs from the exact dimensions.

In FIGURE 7 a jet eductor is shown having a convergent section 70, a straight section 72 and a divergent section 74, with a jet 76 in the convergent section. In this structure, the jet has a diameter d and the straight section has a diameter D. The distance from the tip of the jet to the start of the straight section is a, the length of the straight section is L, and the length of the divergent section is d. The relationship between these parts is critical and must be within the ranges given below. Further, within these ranges, certain dimensions are preferred for optimum results.

D=l.0d to 3.0a, prefer 2.0d L=2D to 10D, prefer 7.0D a=0.5d to 5d, prefer l.1d

Less critical than the above is the length b of the divergent section which should be in the range:

Obviously, many modifications and variations of this invention may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claims.

I claim:

1. Apparatus for removing sea growths from the hulls of vessels while said hulls are under water comprising:

(a) a wheeled carriage having at least three wheels whereby to provide means for maintaining a predetermined orientation of said carriage relative to said hull;

(b) a conduit which is elongated when viewed in plan supported by the said wheels and having generally opposed inlet and outlet ends, said inlet end including a mouth positioned, relative to said wheels, so that, when said wheels rest on a substantially flat surface, said mouth will be spaced from said surfact to permit water to pass between said mouth and said surface in wiping engagement therewith;

(c) a plurality of nozzles in said conduit positioned side-by-side, said nozzles being directed generally toward the outlet end of the said conduit, each nozzle including an elbow therein, said elbow describing an angle of about 75 whereby to provide means for introducing an upward force component reacting against the flow of water through said nozzle when- 'ever the said apparatus is in a substantially vertical orientation;

(d) a hose connected at one end to means connected to each of the said nozzles and adapted for connection to a source of water under pressure at the other end for discharging a jet of water from each of said nozzles into said conduit toward the outlet end thereof whereby to induce a flow of water between said mouth and a surface adjacent thereto; and

(e)a guide means secured by a pivotal connection to either side of the said carriage permitting the said carriage to be guided into contact with the hull of the vessel and to permit said carriage to turn about said pivotal connection whereby all wheels of the said carriage may be brought into contact with said 3 hull, the said guide means having an elongated handle thereon which may be manually manipulated.

2. The structure of claim 1 wherein four wheels are secured about equidistant from one another and secured to the said carriage, said wheels supporting the mouth of the said conduit about A inch from the lowermost edges of said Wheels.

3. Apparatus for removing sea growths from the hull of a vessel while said hull is under water, comprising a Water jet eductor having anti-friction means for carrying the eductor for movement along said hull, said jet eductor having a mouth adapted to be supported in proximity to a hull, said jet eductor having a converging section, a straight section having a diameter D and a length L, a diverging section having a length b with a jet having an opening of diameter d located within the converging section, said jet being located a distance a from the straight section, and being capable of discharging water at an acute angle to said hull, and bendable supply means for supplying high velocity water into said jet eductor, said supply means providing an acute angle to the hull variable to change the net reaction force along the hull, said water acting simultaneously to hold said apparatus against said hull and creating a reduced pressure area in the converging section to clean said hull, said parts having the relationship:

4. The structure of claim 3 wherein the relationship is:

5. The structure of claim 3 wherein the length b is 10 from 5D to 15D.

6. The structure of claim 3 wherien the angle of the wall of the convergent section with the axis of the apparatus is from 30 to 50, the angle of the divergent section is from 4 to 8, and the internal angle of the jet wall is 15 from 8 to 15.

References Cited by the Examiner UNITED STATES PATENTS MILTON BUCHLER, Primary Examiner.

D. P. NOON, B. BELKIN, Assistant Examiners. 

1. APPARATUS FOR REMOVING SEA GROWTHS FROM THE HULLS OF VESSELS WHILE SAID HULLS ARE UNDER WATER COMPRISING: (A) A WHEELED CARRIAGE HAVING AT LEAST THREE WHEELS WHEREBY TO PROVIDE MEANS FOR MAINTAINING A PREDETERMINED ORIENTATION OF SAID CARRIAGE RELATIVE TO SAID HULL; (B) A CONDUIT WHICH IS ELONGATED WHEN VIEWED IN PLAN SUPPORTED BY THE SAID WHEELS AND HAVING GENERALLY OPPOSED INLET AND OUTLET ENDS, SAID INLET END INCLUDING A MOUTH POSITIONED, RELATIVE TO SAID WHEELS, SO THAT, WHEN SAID WHEELS REST ON A SUBSTANTIALLY FLT SURFACE, SAID MOUTH WILL BE SPACED FROM SAID SURFACT TO PERMIT WATER TO PASS BETWEEN SAID MOUTH AND SAID SURFACE IN WIPING ENGAGEMENT THEREWITH; (C) A PLURALITY OF NOZZLES IN SAID CONDUIT POSITIONED SIDE-BY-SIDE, SAID NOZZLES BEING DIRECTED GENERALLY TOWARD THE OUTLET AND END OF THE SAID CONDUIT, EACH NOZZLE INCLUDING AN ELBOW THEREIN, SAID ELBOW DESCRIBING AN ANGLE OF ABOUT 75* WHEREBY TO PROVIDE MEANS FOR INTRODUCING AN UPWARD FORCE COMPONENT REACTING AGAINST THE FLOW OF WATER THROUGH SAID NOZZLE WHENEVER THE SAID APPARATUS IN A SUBSTANTIALLY VERTICAL ORIENTATION; (D) A HOSE CONNECTED AT ONE END TO MEANS CONNECTED TO EACH OF THE SAID NOZZLES AND ADAPTED FOR CONNECTION TO A SOURCE OF WATER UNDER PRESSURE AT THE OTHER END FOR DISCHARGING A JET OF WATER FROM EACH OF SAID NOZZLES INTO SAID CONDUIT TOWARD THE OUTLET END THEREOF WHEREBY TO INDUCE A FLOW OF WATER BETWEEN SAID MOUTH AND A SURFACE ADJACENT THERETO; AND (E) A GUIDE MEANS SECURED BY A PIVOTAL CONNECTION TO EITHER SIDE OF THE SAID CARRIAGE PERMITTING THE SAID CARRIAGE TO BE GUIDED INTO CONTACT WITH THE HULL OF THE VESSEL AND TO PERMIT SAID CARRIAGE TO TURN ABOUT SAID PIVOTAL CONNECTION THEREBY ALL WHEELS OF THE SAID CARRIAGE MAY BE BROUGHT INTO CONTACT WITH SAID HULL, THE SAID GUIDE MEANS HAVING AN ELONGATED HANDLE THEREON WHICH MAY BE MANUALLY MANIPULATED. 